Question

where is the mistake

Answer 1

The mistake lies in :

2 ( a - b ) = a - b

Upto here its correct since

a = b

==> a - b = 0

2 * 0 = 0

But next step :

2 = 1

This is becoming like 2 * 0 = 1 * 0

                              = 2 = 1

But you cannot divide both sides by 0 in that case.

Hence the last step is wrong because a - b = 0

Hope it helps :)

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